Project Outline:

North Somerset Council appointed Walters to carry out works to South Road in Weston-Super-Mare, starting in April 2024.

The purpose of the work was to strengthen the existing substandard retaining wall. Stabilising the wall would involve a soil nailing scheme for the 70m long stretch of failing wall. The project also involved full depth reconstruction of 40m of footway, and resurfacing of a further 44m of footway.

Project Delivery:

At the beginning of the project 15m of the retaining wall was deemed structurally unsafe and requiring partial demolition.  This lead to a new design and additional element of work in constructing a reinforced concrete buttress wall to strengthen the failed section and support the road above.

A complete vehicle road closure was in place for the duration of the project and diversion routes maintained.

During the soil nailing process it became apparent that unknown voids were present in the retained section of wall along the footpath. This resulted in the requirement for injection grouting through the footpath to be completed before the soil nailing could commence. This strengthened the ground to the rear of the wall and ensured the installed soil nails would fulfil the design requirements.  Walters also installed sub-horizontal drains and weepholes to allow for drainage and avoid saturation.

167 Soil nails, ranging from 6m to 8m long, were then installed to strengthen the wall. Walters suggested a value engineering option to change the proposed stainless-steel nails to galvanised nails which saved the project £100,000.

Walters resurfaced 44m of the footway, and reconstructed 15m of parapet wall. Additional surface water drainage was installed and the carriageway was resurfaced.

Added Value & Client Partnerships

As the project was in a residential area, Walters used an external battery pack to power the welfare and facilities. The battery was charged by a generator which was run from 10am to 3pm. This reduced the noise for residents in the evenings and nights and was a more ecologically and environmentally friendly solution to powering the site.

The project underwent a series of unforeseen changes which were overcome successfully due to effective communication and collaboration between Walters and North Somerset Council.